BIOLOGY 12 12: Digestive System Worksheet Name:________________________ Block__________ 1. Food is received by the ____________________, which possesses ________________ to grind and break up particles. _______________ glands secrete ________________ that moisten food and binds it together for swallowing. The taste of food is detected by _________________ located on the _________________. 2. At the back of the mouth, the muscular ____________________ is involved in swallowing food. The epiglottis folds over the glottis during the swallowing ________________. 3. The esophagus propels food toward the __________________, using muscular contractions called _____________________ At the lower end of the esophagus, a muscular ring called a(n) ____________________ regulates the entrance of food to the stomach. 4. The stomach is lined with _______________ that secretes protective ______________. Otherwise, the lining would be injured by the strong _____________ acid secreted by _______________ glands. Gastric juice also contains ____________ that breaks down proteins. 5. The first section of the small intestine is the __________________. It receives secretions from the ____________________ and __________________ and also receives food known as ______________________ from the stomach. 6. The mucosa of the small intestine is folded into ___________________, which, in turn, have projections from individual cells called ____________________________. Proteins in the microvilli transport nutrients such as ______________________ directly into the bloodstream, and fats must be reconstructed so they can travel into vessels of the lymphatic system called _______________________________. 7. A number of hormones control the secretions of digestive juices. _________________ is secreted in response to protein in foods and enhances gastric gland output, while _____________ inhibits gastric secretions. _________________ is secreted in response to acidic chyme. When fats are present in chyme, __________________ triggers the release of bile from the gallbladder. 8. The large intestine functions to store and compact _________________. Unusual outgrowths of the lining of the colon, called ___________________, can be either benign or cancerous. Colon cancer incidence increases for people who do not have enough __________________ in their diet. 9. Pancreatic juice contains a mix of __________________ solution to neutralize stomach acid, and digestive __________________ to further break down food. 10. The liver produces a greenish substance called ______________________, which is stored and concentrated by the ____________________. The liver has been called the _____________ to the blood because it detoxifies substances entering the blood from the ___________________. 11. ________________________ is a fat-digesting enzyme produced by the accessory organ, the ________________. Starch digestion begins in the _______________ with salivary _________ and continues in the __________________ with pancreatic ____________________. 12. Protein digestion begins in the _________________ where the enzyme _________________ is produced, and continues in the small intestine with the aid of the enzyme _________________ from the pancreas.